If you Knock The Spots Off it means you’ve won easily, without much effort. The expression is of American origin, from the mid-19th century. At carnivals, fairs and festivals all over the country, one of the most popular side shows was the shooting gallery, where cowboys, farmers and children would all pit their skills on the firing range. Playing cards were the most commonly used target, and each sharpshooter would aim to remove as many of the “spots” on the card as possible. The one who shot them all off would be as the winner.